X-Git-Url: https://git.r.bdr.sh/rbdr/ngx_http_office_hours_filter_module/blobdiff_plain/fa2b280d41f583da217a5bdccea67e87cdadffb6..refs/tags/1.0.1:/ngx_http_office_hours_filter_module.c diff --git a/ngx_http_office_hours_filter_module.c b/ngx_http_office_hours_filter_module.c index 5175364..49fe50f 100644 --- a/ngx_http_office_hours_filter_module.c +++ b/ngx_http_office_hours_filter_module.c @@ -11,7 +11,6 @@ * specific language governing permissions and limitations under the License. */ - #include #include #include @@ -20,6 +19,24 @@ * Declarations */ +/* Constants */ + +const ngx_uint_t WEEK_LENGTH = 7; +const char * CLOSED_TOKEN = "closed"; +const ngx_str_t TIME_REGEX = ngx_string("([0-9]{1,2})(?:\\:([0-9]{2}))?\\-([0-9]{1,2})(?:\\:([0-9]{2}))?"); +const ngx_str_t HEAD_HTML = ngx_string("This website is currently closed!

This website is currently closed!

This website has closed for the day, please check our office hours below

"); +const ngx_str_t MIDDLE_HTML = ngx_string("

Current Server Time is: "); +const ngx_str_t FOOT_HTML = ngx_string("

"); +const char * DAY_NAMES[7] = { + "Monday", + "Tuesday", + "Wednesday", + "Thursday", + "Friday", + "Saturday", + "Sunday" +}; + /* Main Configuration Structure */ typedef struct { @@ -30,7 +47,7 @@ typedef struct { static void *ngx_http_office_hours_create_conf(ngx_conf_t * cf); static char *ngx_http_office_hours_merge_conf(ngx_conf_t * cf, - void *parent, void *child); + void *parent, void *child); static ngx_int_t ngx_http_office_hours_init(ngx_conf_t * cf); /* Configuration Handler */ @@ -38,10 +55,27 @@ static ngx_int_t ngx_http_office_hours_init(ngx_conf_t * cf); static char *ngx_http_office_hours(ngx_conf_t * cf, ngx_command_t * cmd, void *conf); -/* Body Filter Storage */ +/* Filter Storage */ +static ngx_http_output_header_filter_pt ngx_http_next_header_filter; static ngx_http_output_body_filter_pt ngx_http_next_body_filter; +/* Utility Functions */ +static ngx_uint_t ** parse_office_hours(ngx_array_t * office_hours); +static ngx_uint_t * parse_office_hours_string(ngx_str_t office_hours); +static ngx_flag_t within_office_hours(ngx_uint_t ** office_hours); +static ngx_uint_t get_day_of_week(time_t time); +static ngx_uint_t get_seconds_of_day(time_t time); +static ngx_uint_t parse_number(ngx_str_t string, ngx_uint_t start, ngx_uint_t end); +static ngx_str_t create_output_html(ngx_http_office_hours_conf_t * conf); +static char * format_hours(ngx_uint_t * seconds, char * day); +static char * format_seconds(ngx_uint_t seconds); +static char * left_pad(unsigned int number); + +/* Globals */ +ngx_regex_compile_t rc; +ngx_str_t OUTPUT_HTML; + /* * Module Definitions */ @@ -51,7 +85,7 @@ static ngx_http_output_body_filter_pt ngx_http_next_body_filter; static ngx_command_t ngx_http_office_hours_commands[] = { { ngx_string("office_hours"), - NGX_HTTP_SRV_CONF | NGX_HTTP_LOC_CONF | NGX_CONF_1MORE, + NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_HTTP_LOC_CONF | NGX_CONF_TAKE1 | NGX_CONF_TAKE2 | NGX_CONF_TAKE3 | NGX_CONF_TAKE4 | NGX_CONF_TAKE5 | NGX_CONF_TAKE6 | NGX_CONF_TAKE7, ngx_http_office_hours, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_office_hours_conf_t, office_hours), @@ -61,7 +95,6 @@ static ngx_command_t ngx_http_office_hours_commands[] = { ngx_null_command }; - /* Module Context */ static ngx_http_module_t ngx_http_office_hours_filter_module_ctx = { @@ -78,7 +111,6 @@ static ngx_http_module_t ngx_http_office_hours_filter_module_ctx = { ngx_http_office_hours_merge_conf /* Merge location configuration */ }; - /* Module Definition */ ngx_module_t ngx_http_office_hours_filter_module = { @@ -96,26 +128,78 @@ ngx_module_t ngx_http_office_hours_filter_module = { NGX_MODULE_V1_PADDING }; +/* + * Main Header Filter + * If the current time is within office hours, it goes to the next + * handler. Otherwise it sets the headers to 403 + */ + +static ngx_int_t +ngx_http_office_hours_header_filter(ngx_http_request_t * r) +{ + + ngx_uint_t ** parsed_office_hours; + ngx_http_office_hours_conf_t *conf; + + conf = + ngx_http_get_module_loc_conf(r, + ngx_http_office_hours_filter_module); + + if (conf->office_hours == NULL) { + ngx_log_error(NGX_LOG_DEBUG, r->connection->log, 0, + "Office hours disabled"); + return ngx_http_next_header_filter(r); + } + + parsed_office_hours = parse_office_hours(conf->office_hours); + + if (within_office_hours(parsed_office_hours)) { + ngx_log_error(NGX_LOG_DEBUG, r->connection->log, 0, + "Within office hours"); + return ngx_http_next_header_filter(r); + } + + ngx_log_error(NGX_LOG_DEBUG, r->connection->log, 0, + "Outside office hours"); + + if (OUTPUT_HTML.data == NULL) { + OUTPUT_HTML = create_output_html(conf); + } + + r->headers_out.status = NGX_HTTP_FORBIDDEN; + r->headers_out.content_length_n = OUTPUT_HTML.len; + + return ngx_http_next_header_filter(r); +} /* * Main Body Filter * If the current time is within office hours, it goes to the next - * handler. Otherwise it returns 403 and the office hour listing. + * handler. Otherwise it replaces the body with the office hours. */ static ngx_int_t -ngx_http_office_hours_body_filter(ngx_http_request_t * r, ngx_chain_t * in) +ngx_http_office_hours_body_filter(ngx_http_request_t * r, ngx_chain_t *in) { + ngx_buf_t *b; + ngx_uint_t ** parsed_office_hours; + ngx_chain_t out; ngx_http_office_hours_conf_t *conf; - ngx_uint_t i; - ngx_str_t *hours; conf = ngx_http_get_module_loc_conf(r, ngx_http_office_hours_filter_module); if (conf->office_hours == NULL) { + ngx_log_error(NGX_LOG_DEBUG, r->connection->log, 0, + "Office hours disabled"); + return ngx_http_next_body_filter(r, in); + } + + parsed_office_hours = parse_office_hours(conf->office_hours); + + if (within_office_hours(parsed_office_hours)) { ngx_log_error(NGX_LOG_DEBUG, r->connection->log, 0, "Within office hours"); return ngx_http_next_body_filter(r, in); @@ -124,15 +208,28 @@ ngx_http_office_hours_body_filter(ngx_http_request_t * r, ngx_chain_t * in) ngx_log_error(NGX_LOG_DEBUG, r->connection->log, 0, "Outside office hours"); - hours = conf->office_hours->elts; + if (OUTPUT_HTML.data == NULL) { + OUTPUT_HTML = create_output_html(conf); + } - for (i = 0; i < conf->office_hours->nelts; ++i) { - ngx_log_error(NGX_LOG_DEBUG, r->connection->log, 0, - (const char *) hours[i].data); + b = ngx_pcalloc(r->pool, sizeof(ngx_buf_t)); + if (b == NULL) { + ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "Failed to allocate response buffer."); + return NGX_HTTP_INTERNAL_SERVER_ERROR; } - r->keepalive = 0; - return NGX_HTTP_FORBIDDEN; + out.buf = b; + out.next = NULL; + + b->start = OUTPUT_HTML.data; + b->pos = b->start; + b->end = OUTPUT_HTML.data + OUTPUT_HTML.len; + b->last = b->end; + + b->memory = 1; + b->last_buf = 1; + + return ngx_http_next_body_filter(r, &out); } /* @@ -147,9 +244,8 @@ static char *ngx_http_office_hours(ngx_conf_t * cf, ngx_command_t * cmd, char *conf_structure = conf; + ngx_str_t *hours, *value; ngx_array_t **office_hours; - ngx_str_t *hours; - ngx_str_t *value; ngx_uint_t i; /* Gets the array from the config structure using the defined @@ -180,7 +276,6 @@ static char *ngx_http_office_hours(ngx_conf_t * cf, ngx_command_t * cmd, return NGX_CONF_OK; } - /* * Config Creator * Initializes the configuration structure @@ -208,7 +303,7 @@ static void *ngx_http_office_hours_create_conf(ngx_conf_t * cf) */ static char *ngx_http_office_hours_merge_conf(ngx_conf_t * cf, - void *parent, void *child) + void *parent, void *child) { ngx_http_office_hours_conf_t *prev = parent; @@ -219,6 +314,247 @@ static char *ngx_http_office_hours_merge_conf(ngx_conf_t * cf, return NGX_CONF_OK; } +/* + * Parse the office hour strings in the configuration file + * to fill out the hours array (in seconds) + */ + +static ngx_uint_t ** parse_office_hours(ngx_array_t * office_hours) +{ + + ngx_str_t *hours; + ngx_uint_t ** parsed_office_hours; + ngx_uint_t i, j; + + parsed_office_hours = malloc(7 * sizeof(ngx_uint_t *)); + + hours = office_hours->elts; + + /* + * On the configuration file, the leftmost element + * always applies to all remaining days, all others + * are read from right to left. So first we will apply + * the initial override, and then iterate based on the + * number of overrides + */ + + for (i = 0; i < WEEK_LENGTH + 1 - office_hours->nelts; ++i) { + parsed_office_hours[i] = parse_office_hours_string(hours[0]); + } + + for (i = 1; i < office_hours->nelts; ++i) { + j = WEEK_LENGTH - office_hours->nelts + i; + parsed_office_hours[j] = parse_office_hours_string(hours[i]); + } + + return parsed_office_hours; +} + +/* + * Given a time string or the closed token, return a tuple + * of numbers representing opening and closing hours + */ + +static ngx_uint_t * parse_office_hours_string(ngx_str_t office_hours) +{ + + int captures[(1 + 4) * 3]; + ngx_int_t n; + ngx_uint_t * parsed_hours; + + parsed_hours = malloc(2 * sizeof(ngx_uint_t)); + + if(ngx_strcmp(office_hours.data, CLOSED_TOKEN) == 0) { + parsed_hours[0] = 0; + parsed_hours[1] = 0; + return parsed_hours; + } + + n = ngx_regex_exec(rc.regex, &office_hours, captures, (1 + 4) * 3); + + if (n >= 0) { + /* Opening Hours */ + + parsed_hours[0] = 60 * 60 * parse_number(office_hours, captures[2], captures[3]); + parsed_hours[0] = parsed_hours[0] + 60 * parse_number(office_hours, captures[4], captures[5]); + + parsed_hours[1] = 60 * 60 * parse_number(office_hours, captures[6], captures[7]); + parsed_hours[1] = parsed_hours[1] + 60 * parse_number(office_hours, captures[8], captures[9]); + + return parsed_hours; + } + + /* Non-matching strings count as open */ + + parsed_hours[0] = 0; + parsed_hours[1] = 86400; + return parsed_hours; +} + +/* + * Given an office hours array, it returns whether or not + * it is currently within office hours. + */ + +static ngx_flag_t within_office_hours(ngx_uint_t ** office_hours) +{ + + time_t now; + ngx_uint_t day_of_week, seconds_of_day; + ngx_uint_t * current_hours; + + ngx_time_update(); + now = ngx_time(); + day_of_week = get_day_of_week(now); + seconds_of_day = get_seconds_of_day(now); + current_hours = office_hours[day_of_week]; + + return seconds_of_day >= current_hours[0] && seconds_of_day <= current_hours[1]; +} + +/* + * Calculate the day of the week given a timestamp + */ + +static ngx_uint_t get_day_of_week(time_t time) +{ + + /* Epoch was thursday, so add 3 so we start on monday */ + return (time / 86400 + 3) % 7; +} + +/* + * Calculate the number of seconds elapsed today + */ + +static ngx_uint_t get_seconds_of_day(time_t time) +{ + + return time - (time / 86400) * 86400; +} + +/* + * Parses a string, returns 0 if match was not found + */ + +static ngx_uint_t parse_number(ngx_str_t string, ngx_uint_t start, ngx_uint_t end) +{ + + if (end - start == 0) { + return 0; + } + + return ngx_atoi(&string.data[start], end - start); +} + +/* + * Given the current office hours configuration it creates the custom + * HTML + */ + +static ngx_str_t create_output_html(ngx_http_office_hours_conf_t * conf) +{ + + char * output_buffer; + time_t now; + ngx_str_t output_html; + ngx_uint_t i, seconds_of_day; + ngx_uint_t ** parsed_office_hours; + + output_buffer = malloc(1024 * sizeof(char)); + parsed_office_hours = parse_office_hours(conf->office_hours); + now = ngx_time(); + seconds_of_day = get_seconds_of_day(now); + + sprintf(output_buffer, "%s", (char *) HEAD_HTML.data); + + for (i = 0; i < 7; ++i) { + sprintf(output_buffer + strlen(output_buffer), "%s", format_hours(parsed_office_hours[i], (char *) DAY_NAMES[i])); + } + + sprintf(output_buffer + strlen(output_buffer), "%s", (char *) MIDDLE_HTML.data); + sprintf(output_buffer + strlen(output_buffer), "%s", format_seconds(seconds_of_day)); + sprintf(output_buffer + strlen(output_buffer), "%s", (char *) FOOT_HTML.data); + + output_html.data = (unsigned char *) output_buffer; + output_html.len = strlen(output_buffer); + + return output_html; +} + +/* + * Given a tuple of seconds and a day name, outputs an HTML + * string containing the formatted data as a list item + */ + +static char * format_hours(ngx_uint_t * hours, char * day) +{ + + char * output_html; + + output_html = malloc(64 * sizeof(char)); + if (hours[0] == hours[1]) { + sprintf(output_html, "

%s: CLOSED

", + day + ); + return output_html; + } + + sprintf(output_html, "

%s: %s - %s

", + day, + (char *) format_seconds(hours[0]), + (char *) format_seconds(hours[1]) + ); + + return output_html; +} + +/* + * Given seconds of the day, it returns a string showing + * HH:MM in 24 hour format + */ + +static char * format_seconds(ngx_uint_t seconds) +{ + + char * output_html; + unsigned int hours, minutes; + + output_html = malloc(6 * sizeof(char)); + + hours = seconds / 60 / 60; + minutes = (seconds / 60) % 60; + + sprintf(output_html, "%s:%s", + left_pad(hours), + left_pad(minutes) + ); + + return output_html; +} + +/* + * Returns a number as a string adding 0 if < 10 + */ + +static char * left_pad(unsigned int number) +{ + + char * output_string; + char * padding; + + padding = ""; + output_string = malloc(4 * sizeof(char)); + + if (number < 10) { + padding = "0"; + } + + snprintf(output_string, 4, "%s%u", padding, number); + + return output_string; +} + /* * Postconfig Initialization Handler * Sets the request filter at the top of the chain @@ -227,8 +563,17 @@ static char *ngx_http_office_hours_merge_conf(ngx_conf_t * cf, static ngx_int_t ngx_http_office_hours_init(ngx_conf_t * cf) { + ngx_http_next_header_filter = ngx_http_top_header_filter; + ngx_http_top_header_filter = ngx_http_office_hours_header_filter; + ngx_http_next_body_filter = ngx_http_top_body_filter; ngx_http_top_body_filter = ngx_http_office_hours_body_filter; + rc.pattern = TIME_REGEX; + rc.pool = cf->pool; + if (ngx_regex_compile(&rc) != NGX_OK) { + return NGX_ERROR; + } + return NGX_OK; }